Add conditional checks to _check_and_adjust_attn_implementation() (huggingface#41542)

Author: zheliuyu

src/transformers/modeling_utils.py

@@ -2499,6 +2499,7 @@ def _check_and_adjust_attn_implementation(
             and self._supports_flash_attn
             and not (is_flash_attn_2_available() or is_flash_attn_3_available())
             and is_kernels_available()
+            and not is_torch_npu_available()
         ):
             if attn_implementation.endswith("2"):
                 applicable_attn_implementation = "kernels-community/flash-attn"